How do we know special revelation is necessary for salvation?

Special revelation is essential for salvation because it conveys the specific knowledge of God's redemptive plan revealed through Jesus Christ. While general revelation, as seen in creation and conscience, informs all humanity of God's existence (Romans 1:20), it does not provide the means for salvation or a relationship with the Creator. John 17:3 emphasizes that eternal life is knowing the only true God and Jesus Christ, the one He sent. Thus, salvation requires the deeper understanding provided by special revelation—how God reconciles His justice and mercy through Christ’s atoning sacrifice.